An elder in my church was diagnosed with cancer. I set up my old system (which was on a hot tub) at the edge of her kitchen, and had her drink at least 2 glasses of freshly ozonated water daily in hopes of slowing down the cancer.
3 weeks later, she told me at church that the doctor couldn't find any traces of the cancer.
I recommended that she keep drinking the O3 water to keep the cancer from coming back. She did NOT want a newer machine. (The improvised box for the old unit takes up about 2 square feet of counter space)
She said "That one got rid of my cancer, and that is the one I'm gonna keep using" However, she ordered over a dozen units over 2 years to distribute among her friends. Ozone appeared to work beyond my expectations.